FIELD OF THE INVENTION
[0001] The present invention relates to photographic silver halide emulsions, silver halide
photographic light sensitive materials, and in particular to silver halide emulsions
containing tabular grains and photographic materials having enhanced sensitivity and
superior storage stability.
BACKGROUND OF THE INVENTION
[0002] In camera speed silver halide photographic materials is conventionally employed silver
iodobromide in terms of the ratio of sensitivity to glanularity. Recently, in response
to requirements for enhanced high-speed processing in the photographic field, it has
been desired to reduce the iodide contained in silver halides which exhibit the characteristic
of retarded development. In photographic print materials, on the other hand, silver
chloride emulsions have been employed. As is well known, silver chloride has the characteristic
for promoting development, but it has not been suitable in terms of the ratio of sensitivity
to glanularity.
[0003] JP-A 10-123641 (herein, the term, JP-A means an unexamined and published Japanese
Patent Application) discloses (111) tabular grains mainly comprised of silver iodobromide
and including dislocation lines, which further comprises a silver chloride shell.
Thus, although it is disclosed that silver chloride is indispensably incorporated
for the purpose of covering the whole grain, nothing is taught therein with respect
to forming an annular band. Further, nor is anything disclosed with respect to the
necessity of containing iodide. JP-A 5-53232 discloses a technique of providing a
new function by converting a chloride containing portion to a different silver halide.
However, there is not taught anything with respect to the merit of converting at least
a part of the chloride to iodide in the annular band formed in (1119 tabular grains.
JP-A 8-254779 and 8-254780 disclose a technique of forming high chloride annular band
in the tabular grains. Again, nothing is taught therein with respect to the advantage
of allowing iodide to be contained in the annular band portion.
SUMMARY OF THE INVENTION
[0004] Accordingly, it is an object of the present invention to provide silver halide emulsions
having enhanced sensitivity and superior storage stability and silver halide photographic
light sensitive materials by use thereof.
[0005] The object of the invention can be accomplished by the following constitution:
1. a silver halide emulsion comprising tabular silver halide grains, wherein said
tabular grains contain 50 mol% or more bromide, based on total silver and have parallel
(111) major faces and a mean aspect ratio of not less than 2; and the tabular grains
each comprising a central region accounting for at least 50% of the (111) major face,
and an annular band accounting for not more than 5% of the (111) major face and containing
not less than 0.05 mol% iodide and not more than 50 mol% chloride, based on silver
forming the annular band; and
2. a method of preparing a silver halide emulsion comprising tabular grains, wherein
said tabular grains contain 50 mol% or more bromide, based on total silver and have
parallel (111) major faces and a mean aspect ratio of not less than 2; and the tabular
grains each comprising a central region accounting for at least 50% of the (111) major
face, and an annular band accounting for not more than 5% of the (111) major face
and containing not less than 0.05 mol% iodide and not more than 50 mol% chloride,
based on silver forming the annular band, the method comprising the steps of:
(a) reacting silver and a halide salts in solution to form tabular grains substantially
not containing chloride,
(b) reacting a silver salt solution and a chloride containing halide salt solution
to form the annular band containing chloride and
(c) adding a water soluble iodide salt to perform conversion of at least a part of
the chloride to iodide.
BRIEF EXPLANATION OF THE DRAWING
[0006] Fig. 1a shows a plan view of the tabular grain, indicating the central region 2 and
the annular band 3.
[0007] Figs. 1b and 1c each show a sectional view of the section 1-1'.
DETAILED DESCRIPTIONOF THE INVENTION
[0008] According to the present invention, retardation in development due to iodides can
be avoided by maintaining a relatively low iodide content on the major faces and stability
can also be kept by allowing iodide to be contained in the annular band. Development
is further promoted by allowing chloride to be contained in the annular band, without
adversely affecting adsorption of a sensitizing dye onto the major faces.
[0009] The present invention will be further described in detail. The silver halide emulsion
according to the invention comprises tabular grain having parallel (111) major faces.
The tabular grains preferably exhibit an aspect ratio of not more than 2 and contain
at least 50 mol% bromide. The tabular grains are each comprised of parallel, (111)
major faces and side faces connecting the major faces. At least one twin plane is
present between the major faces and conventionally, two twin planes are observed.
The spacing between the two twin planes can be reduced to less than 0.012 µm, as described
in U.S. Patent 5,219,720, and the value of the spacing between the (111) major faces
divided by the spacing between the twin planes, as described in JP-A 5-249585.
[0010] In the emulsion, tabular grains having an aspect ratio of 2 or more preferably account
for at least 30% of the total grain projected area. The grain projected area and aspect
ratio of the tabular grains can be determined from shadowed electronmicrographs obtained
by the carbon replica method using latex balls as reference. When viewed from the
top, the tabular grains conventionally exhibit hexagonal, triangular or spherical
shape. The aspect ratio is the value of an equivalent circular diameter (i.e., a diameter
of a circle having an area identical to the projected area) divided by the thickness
of the grain. The tabular grains preferably have a hexagonal form, in which the adjacent
edge ratio of the hexagonal grains is preferably 1:2 or less (in other words, the
maximum adjacent edge ratio is 2). The desired effects of the invention can be achieved
by tabular grain having an aspect ratio of 2 or more, irrespective of its value. At
least 30% of the total grain projected area of the tabular grain emulsion is preferably
accounted for by tabular grains having an aspect ratio of not less than 2, and more
preferably 2 to 20. When the aspect ratio is too large, a coefficient of variation
of grain size frequency distribution tends to be increased. The coefficient of variation
of grain size frequency distribution is preferably not more than 20%, and more preferably
not more than 15%.
[0011] The emulsion according to the invention comprises silver iodochlorobromide grains.
The tabular grains according to the invention each are comprised of regions different
in the halide composition, in which one of the regions is a central region, and a
second region is an annular band. The central region of the tabular grain preferably
contains not more than 15 mol% iodide and more preferably not more than 10 mol% iodide.
The annular band portion of the grain preferably contains not more than 50 mol% (and
more preferably from 0.1 to 50 mol%) chloride, and preferably containing not less
than 0.05 mol% iodide. A coefficient of variation of the chloride content distribution
among grains is preferably not more than 20%, and more preferably not more than 10%.
[0012] The central region is preferably in a hexagonal form within the major face of the
tabular grain, in which the hexagonal form is the same as defined in the hexagonal
tabular grains. The annular band is preferably an outer region adjacent to the hexagonal
central region. In other words, the central region and the annular band each extend
between and form a portion of the (111) major faces. The center of gravity of the
hexagonal tabular grain is usually the same as that of the central region of the hexagonal
tabular grain, but both centers of gravity may deviate from each other when forming
the annular region. For example, the growth behavior of hexagonal tabular grains is
reported in the Journal of Imaging Science
31 15 (1987), in which Photograph 9 illustrates deviation of the center of gravity.
[0013] The central region and the annular band portion, each forms a portion of the (111)
major faces. The central region accounts preferably not less than 50% of the (111)
major face; and the annular band accounts preferably not more than 5% of the (111)
major faces, and more preferably not less than 0.5% and not more than 5% of the (111)
major faces. The central region and the annular band each extend between and form
a portion of the (111) major faces.
[0014] Figs. 1a to 1c illustrate the tabular grain according to the invention. Fig. 1a shows
a plan view of the tabular grain, indicating the central region 2 and the annular
band 3. Figs. 1b and 1c each show a sectional view of the section 1-1'. Specifically,
Fig. 1b shows an annular band which inwardly extends and Fig. 1c shows an annular
band which outwardly extends.
[0015] The tabular grains having the central region preferably contain dislocation lines.
The location of the dislocation lines is not specifically limited but the dislocation
lines are preferably located in the central region. It is also preferred that the
dislocation lines be located in both the central region and the annular band. With
respect to the number of the dislocation lines, tabular grain containing 5 or more
dislocation lines preferably account for at least 30% of the total projected area
of grains contained in the emulsion. The number of the dislocation lines is more preferably
10 or more per grain. In cases where the dislocation lines are located in the interior
and the fringe portion of the grain, it is preferred that 5 or more dislocation lines
be present in the interior, and more preferably, 5 or more dislocation lines are present
in both the interior and the fringe portion.
[0016] The method for introducing the dislocation lines into the silver halide grain is
not specifically limited. The dislocation lines can be introduced by employing various
methods, in which, at a desired position of introducing the dislocation lines during
the course of forming silver halide grains, an iodide (e.g., potassium iodide) aqueous
solution is added, along with a silver salt (e.g., silver nitrate) solution and without
addition of a halide other than iodide by a double jet technique, silver iodide fine
grains are added, only an iodide solution is added, or a compound capable of releasing
an iodide ion disclosed in JP-A 6-11781 (1994) is employed. Of these methods are preferred
the method of adding the iodide aqueous solution and silver salt aqueous solution
by the double jet technique, the method of adding fine silver iodide grains and the
method of adding the iodide releasing compound. The iodide aqueous solution is preferably
an alkali iodide aqueous solution, and the silver salt aqueous solution is a silver
nitrate aqueous solution.
[0017] The dislocation lines of silver halide grains can be directly observed by means of
transmission electron microscopy at a low temperature, for example, in accordance
with methods described in J.F. Hamilton, Phot. Sci. Eng.
11 (1967) 57 and T. Shiozawa, Journal of the Society of Photographic Science and Technology
of Japan,
35 (1972) 213. Silver halide tabular grains are taken out from an emulsion while making
sure not to exert any pressure that may cause dislocation in the grains, and the grains
are then placed on a mesh for electron microscopy. The sample is observed by transmission
electron microscopy, while being cooled to prevent the grain from being damaged by
electron beam (e.g., printing-out). Since electron beam penetration is hampered as
the grain thickness increases, sharper observations are obtained by using a higher
voltage type electron microscope (e.g., 200 kV or higher for grains having a thickness
of 0.25 µm). From the thus-obtained electron micrograph can be determined the position
and number of the dislocation lines in each grain.
[0018] Silver halide tabular grain emulsions according to the invention can be prepared
by various methods known in the art. In preferred embodiment of the invention, the
emulsion can be prepared by a process comprising (i) reacting silver and a halide
salts in solution to form tabular grains substantially not containing chloride, (ii)
reacting a silver salt solution and a chloride containing halide salt solution to
form the annular band containing chloride and (iii) adding a water soluble iodide
salt to perform conversion of at least a part of the chloride to iodide.
[0019] In the step (i) described above, the tabular grains substantially not containing
chloride are preferably those which contain not more than 5 mol% chloride, more preferably
not more than 1 mol% chloride, and still more preferably not more than 0.3 mol% chloride.
[0020] The annular band containing chloride will now be further described. JP-A 9-319017
discloses that the chloride content in the vicinity of corners which is higher than
the mean overall chloride content of grains, resulted in development promoting effects
and also discloses a technique for forming such grains by partially dissolving tabular
grains to allow the chloride to be included in the corners. However, it was proved
that when grains containing dislocation lines were subjected to such a treatment,
the dislocation lines of lattice defects were destroyed, and it often became difficult
to achieve development promoting effects of silver chloride, while keeping superior
photographic performance. In contrast, forming a chloride containing portion in the
annular band without dissolving the grains made it easier to maintain the dislocation
lines, enabling easy conversion of the chloride to the iodide.
[0021] In the invention, after forming the chloride containing band, it is preferred to
convert a part or the whole of the chloride to iodide by adding an iodide ion such
as potassium iodide. The iodide ion releasing compounds described above may also be
included. Although the chloride containing portion effectively promotes development,
higher solubility of the chloride possibly causes a drop in the stability of performance.
Conversion of a part of the chloride to iodide results in stabilized performance,
while maintaining the advantageous effects of the chloride. If conversion to iodide
is conducted before formation of the chloride containing band, only bromide is converted
to iodide, making it difficult to stabilize the chloride containing band and in addition,
it is hard to form a iodide containing portion within the band. Coexistence of an
iodide ion or silver iodide at the time of forming the chloride containing band can
form an annular band containing both chloride and iodide. In such case, supplying
a silver ion causes preferentially deposition of silver iodide so that the halide
composition in the vicinity of the surface tends to be riche in chloride. Therefore,
to allow iodide to be preferentially contained in the vicinity of the surface to stabilize
performance is preferred halide conversion by using iodide ions.
[0022] The annular band containing chloride is preferred for promoting development and the
central region may also contain chloride. The chloride content of the annular band
may be higher or lower than that of the central region.
[0023] The iodide ion may be added before sensitization or after adding a part or all of
a chemical sensitizer or a spectral sensitizing dye. Addition of an iodide ion affects
adsorption of a sensitizing dye. Thus, effects of the iodide ion on adsorption of
a sensitizing dye are generally different between before or after adding the sensitizing
dye so that the adding sequence may appropriately be selected so as to obtain the
preferred photographic performance. The iodide also affects sulfur sensitization or
selenium sensitization so that addition of the iodide may be conducted in the appropriate
order to achieve preferred photographic performance.
[0024] The chloride content in the annular band can be determined using a transmission electronmicroscope
provided with an elementary analysis device, at a low temperature. The iodide content
in the central region can be determined similarly, or also by X-ray diffractometry.
[0025] Silver halide emulsions according to the invention can be prepared with reference
to Cleave, "Photography Theory and Practice" (1930) page 131; Gutoff, Phot. Sci. Eng.
14 248-257 (1970); U.S. Patent 4,434,226, 4,414,310, 4,433,048 and 4,439,520; British
Patent 2,112,157.
[0026] Preparation of host grains is basically comprised of a combination of nucleation,
ripening and growth. The methods described in U.S. Patent 4,797,354 and JP-A 2-838
are effective for preparing host grains used in the invention.
[0027] The use of gelatin having a low methionine content in nucleation, as described in
U.S. Patent 4,713,320 and 4,942,120; nucleation at a high pBr, as described in U.S.
Patent, 4,914,014 and nucleation conducted over a short period of time, as described
in JP-A 2-222,940 are effective in the nucleation stage of core grains used in the
invention. Techniques of ripening at a low base concentration, as described in U.S.
Patent 5,254,453 and at a high pH, as described in U.S. Patent 5,013,641 are effective
for ripening tabular host grain emulsions used in the invention. The preparation of
tabular grains by the use of polyalkyleneoxide compounds, as described in U.S. Patent
5,147,771, 5,147,772, 5,147,773, 5,171,659 and 5,210,013 is preferably employed in
preparing host grains used in the invention.
[0028] An iodide containing annular band portion is allowed to grow on the tabular grains
according to the method described above. The temperature, the pH, the kind of protective
colloid such as gelatin or its concentration, and a silver halide solvent including
kind and concentration can be broadly varied. The pCl in growing a chloride containing
annular band portion, prior to forming the iodide containing annular band portion
is preferably 3 or less, and more preferably 2 or less. In this case, the pCl means
a logarithm of reciprocal of the chloride ion concentration, assuming that the whole
of bromide ions react with silver ions and any remaining silver ions react with chloride
ions. Instead of the double jet addition of an aqueous silver nitrate solution and
an aqueous halide salt solution, an aqueous silver nitrate solution, an aqueous chloride
and bromide solution and a fine silver iodide grain emulsion may concurrently be added.
The first shell can be formed by adding a fine silver iodobromide grain emulsion to
perform ripening.
[0029] Gelatin is advantageously employed as a protective colloid utilized in preparation
of emulsions used in the invention or as a binder of a hydrophilic colloidal layer.
Other hydrophilic colloids can also be employed. Examples thereof include gelatin
derivatives; graft polymers of gelatin with other polymers, proteins such as albumin
and casein; cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose
and cellulose sulfuric acid ester; saccharide derivatives such as sodium alginate
and starch derivatives; and synthetic hydrophilic polymer materials such as polyvinyl
alcohol, partial acetal of polyvinyl alcohol, poly-N-vinyl pyrrolidone, polyacrylic
acid, polymethacrylic acid, polyacrylamide, polyvinyl imidazole, polyvinyl pyrazole,
and their copolymers.
[0030] Examples of gelatin include alkali process gelatin, acid process gelatin, enzymatic
process gelatin described in Bull. Soc. Sci. Photo. Japan No. 16, page 30 (1966) and
hydrolyzed gelatin.
[0031] Silver halide emulsions used in the invention may be washed for desalting and redispersed
in a newly prepared protective colloid. The washing temperature is optional and preferably
5 to 50° C. The washing pH is optional and preferably 2 to 10, and more preferably
3 to 8. The washing pAg is preferably 5 to 10. Examples of the washing method include
noodle washing, dialysis by using a semi-permeable membrane, centrifugation, coagulation
process and deionization. The coagulation process includes coagulation by use of sulfates,
organic solvents, water-soluble polymers or gelatin derivatives.
[0032] In the course of preparing silver halide emulsions used in the invention, salts of
metal ions are optionally allowed to coexist during grain formation, at the stage
of desalting, during chemical sensitization or before coating. It is preferred that
in cases of doping into the grain, metal salts are added during grain formation; and
in cases of being used for modifying the grain surface or as a chemical sensitizer,
the metal salts are added after grain formation but before completing chemical ripening.
Metals may be doped into the overall grain, only in the core portion or only in the
shell portion. Examples of metals to be doped include Mg, Ca, Sr, Ba, Al, Sc, Y, La,
Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ru, Rh, Pd, Re, Os, Ir, Pt, Au, Cd, Hg, Tl, In, Sn,
Pb and Bi. These metals can be added in the form of a water-soluble salt, such as
ammonium salt, acetate salt, nitrate salt, sulfate salt, phosphate salt, hydroxy salt,
or hexa-coordinated or tetra-coordinated complex salt. Examples thereof include CdBr
2, CdCl
2, Cd(NO
3)
2, Pb(NO
3)
2, Pb(CH
3COO)
2, K
3[Fe(CN)
6], (NH
4)
4[Fe(CN)
6], K
3IrCl
6, (NH
4)
3RhCl
6, and K
4Ru(CN)
6. Ligands of the complex include halo, aquo, cyano, cyanate, thiocyanate, nitrocyl,
thionitrocyl, oxo, and carbonyl. The metal salts may be employed alone or in combination
of two or more kinds of the metal salts.
[0033] The metal salts can be added through solution in water or organic solvents such as
methanol and acetone. A hydrogen halide (e.g., HCl, HBr, etc.) solution or alkali
halide (e.g., KCl, NaCl, KBr, NaBr, etc.) may further be added to enhance stability
of solutions. Acids or bases may optionally be added. The metal salts may be added
before or during grain formation. The metal salts can continuously be added, during
grain formation, by adding the salts to a water-soluble silver salt aqueous solution
(e.g., AgNO
3) or water-soluble halide aqueous solution (e.g., NaCl, KBr, KI, etc.). Alternatively,
a metal salt solution may separately be added. Addition can be conducted by the combined
use of the methods described above.
[0034] There may be added, during grain formation, a chalcogenide compound described in
U.S. Patent 3,772,031. Cyanates, thiocyanates, selenocyanates, carbonates, phosphates
or acetates may be allowed to be present besides sulfur, selenium and tellurium compounds.
[0035] Silver halide grains used in the invention can be subjected to at least one of sulfur
sensitization, selenium sensitization, gold sensitization, palladium sensitization
or other noble metal sensitization, or reduction sensitization at any stage during
the course of preparing silver halide emulsions. A combination of two or more sensitizations
is preferred. Various types of emulsions can be prepared by selecting the stage to
be subjected to chemical sensitization, including a type of occluding chemical sensitization
sites in the interior of the grain, a type of occluding the sites in a shallow position
from the grain surface and a type of forming the sites on the grain surface. The position
of chemical sensitization sites can optionally be selected, and it is generally preferred
to form chemical sensitization sites in the vicinity of the grain surface.
[0036] Preferred chemical sensitization used in the invention includes chalcogenide sensitization
and noble metal sensitization, alone or in combination. The chemical sensitization
can be conducted using an active gelatin described in T.H. James, The Theory of the
Photographic Process, 4th ed., Macmillan (1977), page 67-76; or at a pAg of 5 to 10,
a pH of 5 to 8 and a temperature of 30 to 80° C using any combination of sulfur, selenium,
gold, platinum, palladium and iridium sensitizers, as described in Research Disclosure
vol. 120, April 1974, 12008, Research Disclosure vol. 134, June, 1975, 13452, U.S.
Patent 2,642,361, 3,297,446, 3,772,031, 3,857,711, 3,901,714, 4,266,018 and 3,904,415
and British Patent 1,315,755. In the noble metal sensitization are employed noble
metal salts of gold, platinum, palladium, iridium and the like. Of these, gold sensitization,
palladium sensitization and their combination are preferably employed. In the gold
sensitization can be employed known compounds such as chloroauric acid, potassium
chloroaurate, potassium aurithiocyanate, gold sulfide and gold selenide. Palladium
sensitizers include compounds or salts of palladium metal with a valence of 2 or 4.
[0037] Sulfur sensitizers include hypo (or thiosulfates)thiourea compounds, rhodanine compounds
and sulfur containing compounds described in U.S. Patent 3,857,711, 4,266,018 and
4,054,457. Chemical sensitization can be carried out in the presence of chemical sensitization
aids. As useful chemical sensitization aids, compounds capable of restraining fogging
during chemical sensitization and enhancing sensitivity are known, including azaindenes,
azapyridazines and azapyrimidine. Examples thereof are described in U.S. Patent 2,131,038,
3,411,914 and 3,554,757; JP-A 58-126526; and Duffin, Photographic Emulsion Chemistry,
page 138-143.
[0038] It is preferred to simultaneously employ gold sensitization in the silver halide
emulsions used in the invention. A gold sensitizer is preferably used in an amount
of 1x10
-7 to 1x10
-4 mol, more preferably 1x10
-7 to 1x10
-5 mol per mol of silver halide. Thiocyanates or selenocyanates may preferably be used
in an amount of 1x10
-6 to 5x10
-4 mol per mol of silver halide. Sulfur sensitizers are preferably used in an amount
of 1x10
-7 to 1x10
-4 mol, and more preferably 5x10
-7 to 1x10
-5 mol per mol of silver halide.
[0039] Selenium sensitization is also preferably employed in the silver halide emulsions
used in the invention. In the selenium sensitization are used unstable selenium compounds
known in the art, including colloidal metallic selenium, selenoureas (e.g., N,N-dimethylselenourea,
N,N-diethylselenourea, etc.), selenoketones and selenoamides. Selenium sensitization
is preferably employed in combination with sulfur sensitization or noble metal sensitization,
alone or in combination.
[0040] The silver halide emulsions used in the invention are preferably subjected to reduction
sensitization during grain formation, after grain formation and before or during chemical
sensitization, or after chemical sensitization. Reduction sensitization can be performed
by any one of a method in which reduction sensitizers are added, so-called silver
ripening in which silver halide grains are grown or ripened in an environment at a
pAg of 1 to 7, and high pH ripening in which grain growth or ripening is performed
in an environment at a pH of 8 to 11. These methods may be employed in combination.
[0041] Of the reduction sensitization methods described above, the addition of reduction
sensitizers is preferred in terms of capability of adjusting the levels of reduction
sensitization. The reduction sensitizers include known compounds such as stannous
salts, ascorbic acid and its derivatives, amines and polyamines, hydrazine derivatives,
formamidinesulfinic acid, silanes and boranes. The reduction sensitizers may be used
alone or in combination. Specifically, of these reduction sensitizers are preferred
stannous chloride, thiourea dioxide, dimethylamine borane, and ascorbic acid including
its derivatives, alkynylamine compounds, described in U.S. Patent 5,389,510 are also
effective compounds. The addition amount of the reduction sensitizer, depending of
emulsion making conditions, is preferably 10
-7 to 10
-3 mol per mol of silver halide. The reduction sensitizer can be added through solution
in water or organic solvents such as alcohols, glycols, ketones, esters and amides,
during the grain growth. The reduction sensitizer may be added to a reaction vessel
in advance, and it is preferably added at a time during the grain growth. Adding the
reduction sensitizer to a water-soluble silver salt or alkali halide solution in advance
and using this solution, precipitation of silver halide grains can be performed. The
reduction sensitizer can dividedly or continuously be added over a period of time.
[0042] Oxidizing agents are preferably used in the stage of preparing silver halide emulsions
used in the invention. The oxidizing agents usable in the invention refer to compounds
having function of transforming metallic silver to a silver ion. Specifically, effective
compounds are those capable of transforming fine silver grains produced during the
course of forming silver halide grains or chemical sensitization thereof, to silver
ions. The produced silver ions may form sparing water-soluble silver salts such as
silver halide, silver sulfide and silver selenide, or water-soluble salts such as
silver nitrate. Examples of inorganic oxidizing agents include ozone, hydrogen peroxide
and its adducts, oxyacid salts such as peroxyacid salts, peroxy-complexes, permanganates
and chromates, halogens such as iodine and bromine, perhalogenates, metals of high
valence and thiosulfonic acid. Examples of organic oxidizing agents include quinones
such as p-quinone, organic peroxide such as peracetic acid and perbenzoic acid and
compounds capable of releasing an active halogen (e.g., N-bromsucciimide, chloramine
T, chloramine B). Of these, inorganic oxidizing agents of ozone, hydrogen peroxide
and its adducts, halogens and thiosulfonates and organic oxidizing agents of quinones.
Disulfide compounds are also preferred, as described in European Patent 0627657A2.
The combined use of the above-described reduction sensitization and the above-described
oxidizing agent is one preferred embodiment of the invention, which is optimally conducted
in such a way of using an oxidizing agent, followed by reduction sensitization; its
reverse manner or allowing both to simultaneously coexist. These may be conducted
during the grain formation or chemical sensitization.
[0043] A variety of compounds can be employed in the emulsion used in the invention to prevent
fogging or stabilize photographic performance during the preparation of a photographic
material or its storage. Examples thereof include thiazoles such as benzthiazoles,
nitroimidazoles, nitrobenzimidazoles, chlorobenzimidazoles, bromobenzimidazoles, mercaptothiazoles,
mercaptobenzimidazoles, mercaptothiadiazoles, aminotriazoles, benztriazoles, nitrobenztriazoles,
mercaptotetrazoles (specifically, 1-phenyl-5-mercaptotetrazole); mercaptopyrimidines;
mercaptotriazines; thioketo compounds such as oxazolinethione; azaindenes such as
triazaindenes, tetrazaindenes [specifically, 4-hydroxy-substituted-1,3,3a,7-tetrazaindenes]
and pentazaindenes. These compounds have been known as an antifoggants or stabilizer,
as described in U.S. Patent 3,945,474 and 3,982,947 and JP-B 52-28660 (herein, the
term, JP-B means published Japanese Patent). Preferred compounds are those described
in JP-A 63-212932. Antifoggants or stabilizers can be incorporated at any time of
before, during or after the grain formation; the washing stage or redispersing stage
after washing; before, during or after chemical sensitization; and before coating.
Some of these compounds can be used for the purpose of controlling crystal habit,
restraining grain growth, lowering solubility of grains, controlling chemical ripening
and controlling aggregation of sensitizing dyes other than antifogging or stabilizing
action.
[0044] The silver halide emulsion may be spectrally sensitized to an optional spectral wavelength
with a sensitizing dye. Useful sensitizing dye includes, for example, cyanine dyes,
merocyanine dyes, complex cyanine dyes, complex merocyanine dyes, holopolar cyanine
dyes, hemicyanine dyes, styryl dyes, and hemioxonol dyes. To these dyes, any nucleus
applied to the cyanine dyes may be applied as a basic heterocyclic nucleus. That is
to say, pyrroline nucleus, oxazoline nucleus, thiazoline nucleus, pyrrole nucleus,
oxazole nucleus, thiazole nucleus, selenazole nucleus, imidazole nucleus, tetrazole
nucleus, pyridine nucleus, etc.; and those nuclei fused with an alicyclic hydrocarbon
ring or an aromatic hydrocarbon ring, i.e., indolenin nucleus, benzindolenin nucleus,
indole nucleus, benzoxazole nucleus, naphthoxazole nucleus, benzthiazole nucleus,
naphthothiazole nucleus, benzselenazole nucleus, benzimidazole nucleus, quinoline
nucleus, etc. may be applied. These nuclei may be substituted on a carbon atom thereof.
To merocyanine dyes or complex merocyanine dyes, as a nucleus having a ketomethylene
structure, five-membered or six-membered heterocycle, such as thiohydantoin nucleus,
2-thiooxazolidine-2,4-di-one nucleus, rhodanine nucleus, thiobarbituric acid nucleus,
etc. can be applied.
[0045] These sensitizing dyes can be used alone or in combination. The combined use of the
sensitizing dyes are often employed for the purpose of super-sensitization. Exemplary
examples thereof are described in U.S. Patent 2,688,545, 2,977,229, 3,397,060, 3,522,052,
3,527,641, 3,617,293, 3,628,964, 3,666,480, 3,672,898, 3,679,428, 3,703,3773,769,301,
3,8146093,837,862 and 4,026,707; British Patent 1,344,281 and 1,507,803, JP-B 43-4936
and 53-12375: JP-A 52-110618 and 52-109925.
[0046] Together with the sensitizing dye, there may be incorporated into the emulsion, a
dye having no sensitizing action or a substance absorbing no visible light, each of
which exhibits super sensitization. The sensitizing dyes can be added at any time
during the course of the preparation of emulsions. Although the sensitizing dye is
usually added after completing chemical sensitization and before coating, it can be
conducted in such a way that the sensitizing dye is added together with a chemical
sensitizer to simultaneously achieve spectral sensitization and chemical sensitization,
as described in U.S. Patent 3,628,969 and 4,225,666; the sensitizing dye is added
prior to chemical sensitization; the sensitizing dye is added before completing the
precipitation of silver halide grains to initiate spectral sensitization. Further,
the sensitizing dye can dividedly be added, as described in U.S. Patent 4,225,666;
exemplarily, a part of the sensitizing dye is added prior to chemical sensitization
and the remainder is added after completing chemical sensitization. Furthermore, the
sensitizing dye can be added during the formation of silver halide grains, as described
in U.S. Patent 4,183,756. The sensitizing dye is incorporated preferably in an amount
of 4x10
-6 to 8x10
-3 mol per mol of silver halide, and specifically, in cased of the grain size of 0.2
to 1.2 µm, the amount of 5x10
-5 to 2x10
-3 mol per mol of silver halide.
[0047] To a silver halide emulsions are further incorporated a variety of adjuvants in response
to various objectives. Examples thereof are described in RD-17643 (December, 1978),
RD-18716 (November, 1979) and RD-308119 (December, 1989), as shown below.
Additive |
RD-17643 |
RD-18716 |
RD-308119 |
1. |
Chemical sensitizer |
23 |
648 right |
996 |
2. |
Speed enhancing agent |
|
648 right |
|
3. |
Spectral sensitizer/Supersensitizer |
23-24 |
648 right-649 right |
996-998 |
4. |
Brightening agent |
24 |
|
998 right |
5. |
Antifoggant/stabilizer |
24-25 |
649 right |
998 right-1000 right |
6. |
Light absorbent/Filter dye/UV absorbent |
25-26 |
649 right-650 left |
1003 left-1003 right |
7. |
Antistaining agent |
25 right |
650 left-right |
1002 right |
8. |
Image stabilizer |
25 |
|
1002 right |
9. |
Hardener |
26 |
651 left |
1004 right-1005 left |
10. |
Binder |
26 |
651 left |
1003 right-1004 right |
11. |
Plasticizer/Lubricant |
27 |
650 right |
1006 left-1006 right |
12. |
Coating aid/Surfactant |
26-27 |
650 right |
1005 left-1006 left |
13. |
Antistatic agent |
27 |
650 right |
1006 right-1007 left |
14. |
Matting agent |
|
|
1008 left-1009 left |
[0048] Layer arrangement techniques, silver halide emulsions, dye forming couplers, functional
couplers and various additives applicable to silver halide emulsions used in the invention
and photographic materials by use thereof are described in European Patent 0565096A1
(published in October 13, 1993) and references cited therein, as shown below:
1. Layer arrangement: page 61, line 23-35; page 61, line 41 to page 62 line 14;
2. Interlayer: page 61, line 36-40;
3. Interlayer effect providing layer: page 62, line 15-18;
4. Silver halide composition: page 62, line 21-25;
5. Silver halide crystal habit: page 62, line 26-30;
6. Silver halide grain size: page 62, line 31-34;
7. Silver halide emulsion preparation: page 62, line 35-40;
8. Silver halide grain size distribution: page 62, line 41-42;
9. Tabular grain: page 62, line 43-46;
10. Internal grain structure: page 62, line 47-53;
11. Type of latent image formation of emulsion: page 62, line 54 page 63, line 5;
12. Physical and chemical ripening: page 63, line 6-9;
13. Emulsion blending: page 63, line 10-13;
14. Fogged emulsion: page 63, line 14-31;
15. Light-insensitive emulsion: page 63, line 32-43;
16. Silver coating weight: page 63, line 49-50;
17. Photographic additives: Research Disclosures described above
18. Formaldehyde scavenger: page 64, page 54-57;
19. Mercapto type antifoggant: page 65, line 1-2;
20. Foggant-releasing agent: page 65, line 3-7;
21. Dye: page 65, line 7-10;
22. Coupler (general): page 65, line 11-13;
23. Yellow, magenta and cyan coupler: page 65, line 14-25;
24. Polymer coupler: page 65, line 26-28;
25. Antidiffusible coupler: page 65, line 29-31;
26. Colored coupler: page 65, line 32-38;
27. Functional coupler (general): page 65, line 39-44;
28. Bleach accelerator releasing coupler: page 65, line 45-48;
29. Development accelerator releasing coupler: page 65, line 49-53
30. Other DIR coupler: page 65, line 54 to page 66, line 4;
31. Coupler dispersion: page 66, line 5-28;
32. Antiseptic and antifungal agents: page 66, line 29-33;
33. Kind of photographic material: page 66, line 34-36;
34. Light sensitive layer thickness and swelling speed: page 66, line 40 to page 67,
line 1
35. Backing layer: page 67, line 3-8;
36. Development (general): page 67, line 9-11;
37. Developer, developing agent: page 67, line 12-30;
38. Developer additive: page 67, line 31-44;
39. Reversal development: page 67, line 45-56;
40. Open top area: page 67, line 57 to page 68, line 12;
41. Developing time: page 68, line 13-15;
42. Bleach-fixing, bleaching, fixing: page 68, line 16 to page 69, line 31;
43. Automatic processor: page 69, line 32-40;
44. Wash, rinse, stabilization: page 69, line 41 to page 70, line 18;
45. Replenishment, reuse: page 70, line 19-23;
46. Developer-incorporated material: page 70, line 24-33;
47. Developing temperature: page 70, line 34-38;
48. Lens-fitted film: page 70, line 39-41.
[0049] There can preferably be employed bleaching solutions containing 2-pyridine-carboxylic
acid or 2,6-pyridinedicarboxylic acid, a ferric salt such as ferric nitrate, and persulfate
salt, as described in European Patent 602600. In cases when using this bleaching solution,
it is preferred to intervene stop and washing steps between color developing and bleaching
steps. In this case, the stop solution preferably contains an organic acid such as
acetic acid, succinic acid or maleic acid; and the bleaching solution preferably contains
0.1 to 2 mol/l of an organic acid such as acetic acid, succinic acid, maleic acid,
glutaric acid or adipinic acid to adjust the pH value or prevent bleach-fogging.
[0050] Photographic materials used in the invention may have a magnetic recording layer.
The magnetic recording layer is preferably provided on the side opposite to the photographic
component layers, in which a backing layer, antistatic layer (conductive layer), magnetic
recording layer and lubricating layer are preferably coated in this order from the
support.
[0051] As fine magnetic powder contained in the magnetic recording layer are employed magnetic
metal powder, magnetic iron oxide powder, magnetic Co-doped iron oxide powder, magnetic
chromium dioxide powder and magnetic barium ferrite powder. The magnetic powder can
be prepared by the method known in the art. The optical density of the magnetic recording
layer is preferably not more than 1.5, more preferably not more than 0.2, and still
more preferably not more than 0.1, considering its influences on photographic images.
The optical density can be measured using Densitometer PDA-65 (available from Konica
Corp.), in which light of 436 nm is vertically incident through a blue filter to determine
the absorption. The magnetic recording layer preferably has a magnetic susceptibility
of 3x10
-2 emu or more per m
2 of photographic material. The magnetic susceptibility can be determined using sample-vibrating
type magnetic flux meter VSM-3 (available from Toei Kogyo). Thus, after saturated
with an external magnetic field of 1,000 Oe in the coating direction, the magnetic
flux density (residual flux density) is measured at the time when the external magnetic
field is reduced to zero, and the measured value is converted to the volume of the
magnetic layer contained in m
2 of photographic material. The magnetic susceptibility of less than 3x10
-2 emu/m
2 mat cause troubles in magnetic recording input or output. The magnetic layer thickness
is preferably 0.01 to 20 µm, more preferably 0.05 to 15 µm, and still more preferably
0.1 to 10 µm.
[0052] Preferred binders used in the magnetic recording layer include vinyl resin, cellulose
ester rein, urethane resin, and polyester resin. It is preferred to form the binder
by aqueous coating using an aqueous emulsion, without using an organic solvent. Physical
properties can be adjusted by hardening with a hardener, thermally hardening or electron
beam hardening. Specifically, the use of polyisocyanate type hardeners is preferred.
It is necessary to incorporate abrasives into the magnetic recording layer to prevent
clogging of a magnetic recording head. Non-magnetic metal oxide particles, specifically,
fine alumina particles are preferably employed.
[0053] Supports of the photographic materials used in the invention include polyester film
such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); cellulose
triacetate film, cellulose diacetate film; polycarbonate film; polystyrene film and
polyolefin film. The use of high moisture content polyester, as set forth in JP-A
1-244446, 1-291248, 1-298350, 2-89045, 2-29641, 2-2-181749, 2-214852 and 2-291135
is superior in recovering roll-set curl after processing, even when the support is
made thinner. Preferred supports used in the invention include PET and PEN films.
The thickness thereof is preferably from 50 to 100 µm, and more preferably from 60
to 90 µm.
[0054] In one preferred embodiment of the invention, the photographic material has a conductive
layer containing metal oxide particles, such as ZnO, V
2O
5, TiO
2, SnO
2, Al
2O
3, In
2O
3, SiO
2, MgO, BaO, and MoO
3. The preferred metal oxide particles are those which contain oxygen deficiency or
which contain a small amount of a hetero atom capable of providing a donor to the
metal oxide. Each of them is high in conductivity, and specifically, the later is
preferred in terms of giving no fog. As binder used in the conductive layer or backing
layer is employed the same one as used in the magnetic recording layer described above.
Examples of the lubricating layer provided on the magnetic recording layer include
higher fatty acid esters, higher fatty acid amides, olganosiloxanes, liquid paraffins
and waxes.
[0055] In cases where the photographic materials according to the invention are employed
as camera-speed color photographic roll films, the film width is preferably from ca.
20 to 35 mm, and more preferably ca. 20 to 30 mm, which is not only advantageous in
compactness of cameras and patrones, but also leads to saving natural resources and
spaces for storing processed negative films. The picture-taking area of from 300 to
700 mm
2 (preferably from 400 to 600 mm
2) achieves small format without deteriorating image qualities of final prints, leading
to more compact patrones and cameras. The aspect ratio of the picture-taking area
is not specifically limited, including 1:1 of the conventional 126 size, 1:1.4 of
the half-size, 1:1.5 of the 135 size (standard), 1:1.8 of the high vision type and
1:3 of the panorama type.
[0056] The photographic materials used in the form of roll films are preferably contained
in a cartridge. Typical cartridges include the patrone used in the 135 format. Other
types of cartridges are also employed, as disclosed in Japanese Utility Model open
to public inspection publication No. 58-67329 and 58-195236; JP-A 58-181035, 8-182634;
U.S. Patent 4,221,479, JP-A 1-231045, 2-170156, 2-199451, 2-124564, 2-201441, 2-205843,
2-210346, 2-211443, 2-214853, 2-264248, 3-37645 and 3-37646; U.S. Patent 4,846,418,
4,848,693 and 4,832,275. These are also applicable to "compact photographic roll film
patrone and film camera" disclosed in JP-A 5-210201.
EXAMPLES
[0057] The present invention will be further explained by referring to examples of the emulsion
preparation, emulsions and photographic materials according to the invention, but
the present invention is not limited to these examples.
Example 1
Preparation of seed emulsion T-1
[0058] Emulsion T-1 containing seed crystal grains having two parallel twin planes was prepared
according to the following procedure.
Solution A-1 |
Ossein gelatin |
38.0 g |
Potassium bromide |
11.7 g |
Water to make |
34.0 lit. |
Solution B-1 |
Silver nitrate |
810.0 g |
Water to make |
3815 ml |
Solution C-1 |
Potassium bromide |
567.3 g |
Water to make |
3815 ml |
Solution D-1 |
Ossein gelatin |
163.4 g |
10 wt% compound A methanol solution |
5.5 ml |
Water to make |
3961 ml |
Compound A: HO(CH
2CH
2O)
m[CH(CH
3)CH
2O]
19.8(CH
2CH
2O)
nH (m+n=9.77)
Solution E-1 |
Sulfuric acid (10%) |
91.1 ml |
Solution F-1 |
56% acetic acid aqueous solution, |
in a necessary amount |
Solution G-1 |
Ammonia water (28%) |
105.7 ml |
Solution H-1 |
Potassium hydroxide aqueous solution (10%), |
in a necessary amount |
[0059] Using a stirring apparatus described in JP-A 62-160128, solution E-1 was added to
solution A-1 with vigorously stirring at 30° C and then solutions B-1 and C-1, 279
ml of each were added by the double jet addition at a constant flow rate to form silver
halide nucleus grains. Thereafter, solution D-1 was added, the temperature was raised
to 60° C in 31 min., solution G-1 was added, the pH was adjusted to 9.3 with solution
H-1, and ripening was further conducted for 6.5 min. Then, the pH was adjusted to
5.8 with solution F-1 and the remaining solutions B-1 and C-1 were added by the double
jet addition at an accelerated flow rate over a period of 37 min. and after competing
the addition, the emulsion was immediately desalted according to the conventional
procedure. The resulting seed emulsion was observed by an electron microscope and
the emulsion was comprised monodisperse tabular grains having two parallel twin planes,
equivalent circular diameter (ECD) of 0.72 µm and coefficient of variation of grain
size distribution (COV) of 16%.
[0060] Preparation of emulsion Em-1 comprised of grains which have dislocation lines but
do not have chloride-containing annular band
[0061] Using the seed emulsion T-1 and the following solutions, emulsion Em-1 was prepared.
Solution A-2 |
Ossein gelatin |
519.9 g |
10% compound A methanol solution |
5.5 ml |
Seed emulsion T-1 |
5.3 mole equivalent |
Water to make |
18.0 lit. |
Solution B-2 |
3.5N silver nitrate aqueous solution |
2787 ml |
Solution C-2 |
Potassium bromide |
1020 g |
Potassium iodide |
29.1 g |
Water to make |
2500 ml |
Solution D-2 |
Potassium bromide |
618.5 g |
Potassium iodide |
8.7 g |
Water to make |
1500 ml |
Solution E-2 |
Potassium bromide |
208.3 g |
Water to make |
1000 ml |
Solution F-2 |
56% acetic acid aqueous solution, |
in a necessary amount |
Solution H-2
[0062] A fine grain emulsion of 0.672 mole equivalent, which was comprised of 3.0 wt% gelatin
and fine silver iodide grains )ECD of 0.05 µm) was prepared in the following manner.
To 9942 ml of 5.0% gelatin aqueous solution containing 0.254 mol of potassium iodide
were added 3092 ml aqueous solution containing 10.59 mol silver nitrate and 3092 ml
aqueous solution containing 10.59 mol potassium iodide at a constant flow rate in
35 min. to form fine grains, while the temperature, were maintained at 40° C and the
pH and EAg were not specifically controlled.
Solution I-2 |
Aqueous solution containing thiourea dioxide of 4x10-6 mol/mol silver halide |
10 ml |
Solution J-2 |
Aqueous solution containing sodium ethylthiosulfonate of 2.3x10-5 mol/mol silver halide |
100 ml |
Solution K-2 |
10% Potassium hydroxide aqueous solution, |
in a necessary amount |
[0063] To solution A-2 in a reaction vessel with vigorously stirring at 75° C was added
solution 1-2, and then solutions B-2, C-2 and D-2 were added by the double jet addition
according to Table 1 to grow the seed crystal grains to obtain comparative Emulsion
Em-1. Taking account of the critical growth rate, the flow rates of solutions B-2,
C-2 and D-2 acceleratedly varied according to functional equations so that no fine
grains other than growing grains were formed and no deterioration in grain size distribution
due to Ostwald ripening between grown grains occurred. In the first addition during
the course of the grain growth, the temperature, pAg and pH in the reaction vessel
was controlled to be 75° C, 8.9 and 5.8, respectively. Thus, 65.8% of solution B-2
was added in the first addition; then solution J-2 was added; the temperature in the
reaction vessel was lowered to 40° C in 30 min. and the pAg was adjusted to 10.3;
and the total of solution H-2 was added at a given flow for 2 min., immediately followed
by the second addition. In the second addition, the remainder of solution B-2 was
added, while the temperature, pAg and pH were controlled at 40° C, 10.3 and 5.0, respectively.
To control the pAg and pH, solutions E-2, F-2 and K-2 were optionally added.
Table 1
Added solution |
Time (min) |
Added Amount, based on silver (%) |
Iodide Content (mol%) |
Addition order |
B-2, C-2 |
0.00 |
0.0 |
2.0 |
First Addition |
5.26 |
11.7 |
2.0 |
8.63 |
21.2 |
2.0 |
12.65 |
34.8 |
2.0 |
15.81 |
47.3 |
2.0 |
19.85 |
65.8 |
2.0 |
B-2, D-2 |
0.00 |
65.8 |
1.0 |
Second Addition |
6.23 |
73.8 |
1.0 |
12.62 |
82.5 |
1.0 |
18.67 |
91.1 |
1.0 |
24.42 |
100.0 |
1.0 |
[0064] After completing the grain formation, the emulsion was desalted according to the
method described in JP-A 5-72658 and redispersed with adding gelatin to obtain an
emulsion of a pAg of 8.06, a pH of 5.8 at 40° C. From electronmicroscopic observation
of silver halide grains, it was proved that the emulsion was comprised of monodisperse,
hexagonal tabular grains exhibiting ECD of 1.50 µm, COV of 14% and the mean aspect
ratio of 7.0. Emulsion Em-2 was prepared in a manner similar to Em-1, provided that
potassium iodide was further added in the same amount as in Em-5 described below to
convert the surface bromide to the iodide.
Preparation of emulsions Em-3 to Em-5, each comprised of grains having an iodide containing
annular band of 1%, based on the grain projected area.
[0065] Emulsions Em-3 to Em-5 each were prepared in a manner similar to Em-1, provided before
desalting, a chloride containing annular band was formed according to the following
procedure. Thus, when 98% of solution B-2 was added, the second addition was interrupted;
the pAg was adjusted to 10.3 with solution E-2 and the addition continued with keeping
the same pAg until 98% of solution B-2 was added; and then a small amount of solution
B-2 was added to adjust the pAg to 9.0. NaCl was further added in a molar amount equivalent
to the remainder of solution B-2, based on silver and the remainder of solution B-2
was added while the pAg was kept at 8.5 with solution E-2. At this moment, the chloride
content in the annular band was 50 mol%, based on silver forming the annular band.
Furthermore, IN KI aqueous solution was added in an optimal amount to perform halide
conversion at 50° C over a period of 1 hr. The final chloride and iodide contents
are shown in Table 2.
Table 2
|
Added iodide (mol%, based on chloride) |
Iodide content of annular band* |
Chloride content of annular band* |
Em-3 |
0 |
0% |
50% |
Em-4 |
50 |
25% |
25% |
Em-5 |
100 |
50% |
0% |
Em-4B |
50 |
25% |
25% |
Em-4C |
50 |
25% |
25% |
*: mol%, based on silver forming the annular band |
[0066] In Table 2, emulsion Em-4B was prepared in such a manner that during chemical sensitization
of emulsion Em-3, as described below, halide conversion was performed by adding KI
similarly to Em-4, after adding a sensitizing dye and before adding a chemical sensitizer.
Similarly, emulsion Em-4C was prepared through halide conversion by adding KI at 1
min. after adding the chemical sensitizer.
[0067] Emulsion Em-6 comprising grains having iodide-containing band of 1%, based the projected
area, was prepared according to the following procedure. Thus, in the formation of
the chloride-containing annular band of Em-3, instead of adding NaCl in a molar amount
equivalent to the remainder of solution B-2, based on silver, KI of 25 mol%, based
on silver was added and the remainder of solution B-2 was added while the pAg was
kept at 9.0 with solution E-2. Prepared emulsion Em-6 was comprised of grains having
an annular band containing mean 25 mol% iodide and accounting for 1% of the projected
area of the major face.
[0068] Emulsion Em-7 comprising grains having an annular band containing iodide and accounting
for 15% of the projected area, was prepared according to the following procedure.
Thus, in the preparation of Em-1, a chloride-containing annular band was formed prior
to desalting, as follows. To the solution E-2 used in the preparation of Em-1, 5.11
g of NaCl was added, and the remainder of solution B-2 was added, while the pAg was
controlled at 8.5. The resulting emulsion was comprised of tabular grains of 1.42
µm ECD, in which the chloride content in the annular band was 1 mol%, based on silver.
Further, halide conversion was performed by adding KI in an amount corresponding 50
mol% of the chloride to obtain emulsion Em-7 comprised of grains having iodide-containing
annular band, which accounted for 15% of the projected area.
Preparation of chemically sensitized emulsion
[0069] Emulsions Em-1, Em-2, Em-3, Em-4, Em-5, Em-6 and Em-7 each were fractionated into
the volume containing 1 mole silver halide. To each fraction were added sensitizing
dyes in the 9th layer, then, 60 mg of KSCN, optimal amounts of a sulfur sensitizer
(sodium thiosulfate) and a gold sensitizer (chloroauric acid) were further added,
and the mixture was raised to a temperature of 50° C and reacted over an appropriate
period of time. Furthermore, 11.44 mg/mol Ag of 1-(3-acetoamidophenyl)-5-mercaptotetrazole
(APMT) and an optimal amount of selenium sensitizer (triphenylphosphine selenide)
were added thereto and the mixture was reacted. After completing the reaction, the
reaction mixture was cooled to 40° C, while 114.4 mg of APMT was added. The resulting
emulsions were denoted as Em-1A, Em-2A, Em-3A, Em-4A, Em-5A, Em-6A and Em-7A.
Preparation of color photographic material
[0070] The following layers having the composition described below were coated on a subbed
cellulose triacetate film support in this order from the support to prepare a multilayered
color photographic material Samples 11 to 19. Silver iodobromide emulsions used in
the layers other than the 9th layer were those which each were optimally chemically
sensitized by adding sensitizing dyes and then further adding triphenylphosphine selenide,
sodium thiosulfate, chloroauric acid and potassium thiocyanate, according to the conventional
manner.
[0071] In the following examples, the addition amount in the silver halide photographic
material was expressed in g per m
2, unless otherwise noted. The coating amount of silver halide or colloidal silver
was converted to silver. With respect to a sensitizing, dye, it was expressed in mol
per mol of silver halide contained in the same layer.
1st Layer; Antihalation Layer |
Black colloidal silver |
0.16 |
UV absorbent (UV-1) |
0.20 |
High boiling solvent (Oil-1) |
0.16 |
Gelatin |
1.23 |
2nd Layer; Interlayer |
Compound (SC-1) |
0.15 |
High boiling solvent (Oil-2) |
0.17 |
Gelatin |
1.27 |
3rd layer; Low speed red-sensitive layer |
Silver iodobromide emulsion (ECD=0.38 µm, 8.0 mol% iodide) |
0.50 |
Silver iodobromide emulsion (ECD=0.27 µm, 2.0 mol% iodide) |
0.21 |
Sensitizing dye (SD-1) |
2.6x10-5 |
Sensitizing dye (SD-2) |
2.6x10-5 |
Sensitizing dye (SD-3) |
3.1x10-4 |
Sensitizing dye (SD-4) |
2.3x10-5 |
Sensitizing dye (SD-5) |
2.8x10-4 |
Cyan coupler (C-1) |
0.35 |
Colored cyan coupler (CC-1) |
0.065 |
Compound (GA-1) |
2.0x10-3 |
High boiling solvent (Oil-1) |
0.33 |
Gelatin |
0.73 |
4th Layer; Medium Speed Red-sensitive Layer |
Silver iodobromide emulsion (ECD=0.52 µm, 8.0 mol% iodide) |
0.62 |
Silver iodobromide emulsion (ECD=0.38 µm, 8.0 mol% iodide) |
0.27 |
Sensitizing dye (SD-1) |
1.3x10'4 |
Sensitizing dye (SD-2) |
1.3x10-4 |
Sensitizing dye (SD-3) |
2.5x10-4 |
Sensitizing dye (SD-4) |
1.8x10-5 |
Cyan coupler (C-1) |
0.24 |
Colored cyan coupler (CC-1) |
0.040 |
DIR compound (D-1) |
0.025 |
Compound (GA-1) |
1.0x10-3 |
High boiling solvent (Oil-1) |
0.30 |
Gelatin |
0.59 |
5th Layer; High Speed Red-sensitive Layer |
Silver iodobromide emulsion G (ECD=1.0 µm, 8.0 mol% iodide) |
1.27 |
Sensitizing dye (SD-1) |
8.5x10-5 |
Sensitizing dye (SD-2) |
9.1x10-5 |
Sensitizing dye (SD-3) |
1.7x10-4 |
Sensitizing dye (SD-4) |
2.3x10-5 |
Cyan coupler (C-2) |
0.10 |
Colored cyan coupler (CC-1) |
0.014 |
DIR compound (D-1) |
7.5x10-3 |
Compound (GA-1) |
1.4x10-3 |
High boiling solvent (Oil-1) |
0.12 |
Gelatin |
0.53 |
6th Layer; Interlayer |
Compound (SC-1) |
0.09 |
High boiling solvent (Oil-2) |
0.11 |
Gelatin |
0.80 |
7th Layer; Low Speed Green-sensitive Layer |
Silver iodobromide emulsion (ECD=0.38 µm, 8.0 mol% iodide) |
0.61 |
Silver iodobromide emulsion (ECD=0.27 µm, 2.0 mol% iodide) |
0.20 |
Sensitizing dye (SD-7) |
5.5x10-4 |
Sensitizing dye (SD-1) |
5.2x10-5 |
Sensitizing dye (SD-12) |
4.8x10-5 |
Magenta coupler (M-1) |
0.15 |
Magenta coupler (M-2) |
0.37 |
Colored magenta coupler (CM-1) |
0.20 |
DIR compound (D-2) |
0.020 |
Compound (GA-1) |
4.0x10-3 |
High boiling solvent (Oil-2) |
0.65 |
Gelatin |
1.65 |
8th Layer; Medium Speed Green-sensitive Layer |
Silver iodobromide emulsion E (ECD=0.59 µm, 8.0 mol% iodide) |
0.87 |
Sensitizing dye (SD-7) |
2.4x10-4 |
Sensitizing dye (SD-8) |
2.4x10-4 |
Magenta coupler (M-1) |
0.058 |
Magenta coupler (M-2) |
0.13 |
DIR compound (D-2) |
0.025 |
DIR compound (D-3) |
0.025 |
High boiling solvent (Oil-2) |
0.50 |
Gelatin |
1.00 |
9th Layer; High Speed Green-sensitive Layer |
Silver iodobromide emulsion (Table 3) |
1.27 |
Sensitizing dye (SD-8) |
1.4x10-4 |
Sensitizing dye (SD-9) |
1.5x10-4 |
Sensitizing dye (SD-10) |
1.4x10-4 |
Sensitizing dye (SD-12) |
7.1x10-5 |
Magenta coupler (M-2) |
0.065 |
Magenta coupler (M-3) |
0.025 |
Colored magenta coupler (CM-2) |
0.025 |
DIR compound (D-3) |
7.0x10-4 |
Compound (GA-1) |
1.8x10-3 |
High boiling solvent (Oil-2) |
0.15 |
Gelatin |
0.46 |
10th Layer; Yellow Filter Layer |
Yellow colloidal silver |
0.08 |
Compound (SC-1) |
0.15 |
Formaline scavenger (FS-1) |
0.20 |
High boiling solvent (Oil-2) |
0.19 |
Gelatin |
1.10 |
11th Layer; Interlayer |
Formaline scavenger (FS-1) |
0.20 |
Gelatin |
0.60 |
12th Layer; Low Speed Blue-sensitive Layer |
Silver iodobromide emulsion (ECD=0.38 µm, 8.0 mol% iodide) |
0.22 |
Silver iodobromide emulsion (ECD=0.27 µm, 2.0 mol% iodide) |
0.10 |
Sensitizing dye (SD-11) |
5.4x10-4 |
Sensitizing dye (SD-12) |
2.0x10-4 |
Yellow coupler (Y-1) |
0.62 |
Yellow coupler (Y-2) |
0.31 |
Compound (GA-1) |
4.5x10-3 |
High boiling solvent (Oil-2) |
0.20 |
Gelatin |
1.27 |
13th Layer; Medium Speed Blue-sensitive Layer |
Silver iodobromide emulsion (ECD=0.59 µm, 8.0 mol% iodide) |
0.90 |
Sensitizing dye (SD-11) |
3.2x10-4 |
Sensitizing dye (SD-12) |
3.2x10-4 |
Yellow coupler (Y-1) |
0.15 |
DIR compound ((D-1) |
0.010 |
High boiling solvent (Oil-2) |
0.046 |
Gelatin |
0.47 |
14th Layer; High Speed Blue-sensitive Layer |
Silver iodobromide emulsion (ECD=1.00 µm, 8.0 mol% iodide) |
0.85 |
Sensitizing dye (SD-11) |
3.2x10-4 |
Sensitizing dye (SD-12) |
3.2x10-4 |
Yellow coupler (Y-1) |
0.11 |
High boiling solvent (Oil-2) |
0.046 |
Gelatin |
0.47 |
15th Layer; First Protective Layer |
Silver iodobromide emulsion (ECD=0.08 µm, 1.0 mol% iodide) |
0.40 |
UV absorbent (UV-2) |
0.030 |
UV absorbent (UV-3) |
0.015 |
UV absorbent (UV-4) |
0.015 |
UV absorbent (UV-5) |
0.015 |
UV absorbent (UV-6) |
0.10 |
Formaline scavenger (FS-1) |
0.25 |
High boiling solvent (Oil-1) |
0.07 |
High boiling solvent (Oil-3) |
0.07 |
Gelatin |
1.04 |
16th Layer; Second Protective Layer |
Polico (methylmethacrylate/ethylmethacrylate/methacrylic acid) |
0.15 |
Polymethylmethacrylate (Av. 3µm) |
0.04 |
Lubricant (WAX-1) |
0.04 |
Fluorinated surfactant (F-1) |
0.01 |
Fluorinated surfactant (F-2) |
0.01 |
Gelatin |
0.55 |
[0072] In addition to the above composition were added coating aid compounds SU-1 and SU-2,
hardeners H-1 and H-2, dyes AI-1, AI-2 and AI-3, stabilizer ST-1, fog restrainer AF-1,
AF-2 and AF-3 comprising two kinds of weight-averaged molecular weights of 10,000,
and antimold DI-1. Gelatins containing a calcium content of 10 ppm or less were used.
[0074] Samples each were sensitometrically exposed to green light, then allowed to stand
under the condition A described below, processed according to the following steps
and evaluated with respect to sensitivity and fog.
[0075] Condition A: over a period of 7 days at 50° C and 80% R.H.
Processing step (38° C): |
Color developing |
3 min. 15 sec. |
Bleach |
6 min. 30 sec. |
Washing |
3 min. 15 sec. |
Fixing |
6 min. 30 sec. |
Washing |
3 min. 15 sec. |
Stabilizing |
1 min. 30 sec. |
Drying |
|
[0076] Composition of a processing solution used in each step is as follows.
Color developing solution |
4-Amino-3-methyl-N-ethyl-N-(β-hydroxy ethyl)aniline sulfate |
4.75 g |
Sodium sulfite anhydride |
4.25 g |
Hydroxylamine 1/2 sulfate |
2.0 g |
Potassium carbonate anhydride |
37.5 g |
Sodium bromide |
1.30 g |
Trisodium nitrilotriacetate (monohydrate) |
2.50 g |
Potassium hydroxide |
1.00 g |
Water to make |
1 liter |
[0077] The pH was adjusted to 10.1.
Bleaching solution |
Ammonium ferric ethylenediaminetetraacetate |
100.0 g |
Diammonium ethylenediaminetetraacetate |
10.0 g |
Ammonium bromide |
150 0 g |
Glacial acetic acid |
10.0 g |
Water to make |
1 liter |
[0078] The pH was adjusted to 6.0 using ammonia water.
Fixing solution |
Ammonium thiosulfate |
175.0 g |
Sodium sulfite anhydride |
8.5 g |
Sodium metasulfite |
2.3 g |
Water to make |
1 liter |
[0079] The pH was adjusted to 6.0 with acetic acid.
Stabilizing solution |
Formalin (37% aqueous solution) |
1.5 cc |
Koniducks (product by Konica Corp.) |
7.5 cc |
Water to make |
1 liter |
[0080] Fog density is represented by a relative value, based on the fog density of Sample
11 which was processed immediately after exposure, being 100. Sensitivity (denoted
as "S") is represented by reciprocal of exposure necessary to give a density of fog
density plus 0.1 and also represented by a relative value, based on the sensitivity
of Sample 11 which was processed immediately after exposure, being 100.
[0081] Results are shown in Table 3 with respect to the sensitivity and fog of samples which
were processed immediately after exposure (denoted before storage) or after exposed
and stored under the condition A (denoted as after storage).
Table 3
Sample No. |
Before Storage |
After Storage |
Remark |
|
S |
Fog |
S |
Fog |
|
No.11 (Em-1A) |
100 |
100 |
80 |
110 |
Comp |
No. 12 (Em-2A) |
90 |
90 |
85 |
90 |
Comp. |
No.13 (Em-3A) |
110 |
100 |
100 |
110 |
Comp. |
No.14 (Em-4A) |
140 |
90 |
130 |
95 |
Inv. |
No.15 (Em-5A) |
130 |
80 |
125 |
80 |
Inv. |
No.16 (Em-4B) |
150 |
90 |
140 |
95 |
Inv. |
No.17 (Em-4C) |
160 |
90 |
150 |
90 |
Inv. |
No.18 (Em-6A) |
110 |
70 |
110 |
70 |
Inv. |
No.19 (Em-7A) |
90 |
70 |
90 |
80 |
Comp. |
[0082] As apparent from Table 3, inventive samples were superior in sensitivity and fog
to comparative samples. It was further proved that the use of tabular grains according
to the invention, which contained dislocation lines, also led to superior results.